Jalaluddin Haqqani, whose group is being hunted by the US in the Pakistan-Afghanistan borderlands. Photograph: Mohammed Riaz/Associated Press

Missiles fired from unmanned aerial drones have killed at least 12 people in a tribal region along Pakistan's border with Afghanistan as the US military steps up its bombardment of suspected al-Qaida linked militants in the area.

All those who died were inside a house in a village just west of the town of Miran Shah in North Waziristan, Pakistani intelligence officials said. The raid was aimed at the so-called Haqqani network, an Afghan group fighting US-led troops across the border. It was not immediately known whether any or all of those killed were militants.

Since the start of this month US drones have carried out more than a dozen missile strikes in North Waziristan, killing at least 60 people, according to an Associated Press tally compiled from Pakistani intelligence reports.

It is the most intense drone bombardment since the US started targeting the tribal regions in this way in 2004, according to the total. The craft are controlled remotely using video links and fire powerful surface-to-air missiles. Their use soared in 2008 and has been steadily climbing since, with nearly 70 attacks this year.

The Pentagon refuses to comment on drone operations. The frequent civilian casualties anger some Pakistanis and the country's government remains opposed to the drones' use. "The position of the army and government is the same, that it harms more than it helps," said an army spokesman, Major General Athar Abbas.

Public resentment of drone strikes is even greater across the border in Afghanistan, particularly after several incidents in which missiles killed large numbers of civilians.

Much of the current bombardment is aimed at the militant network set up by a veteran Afghan mujahideen leader Jalaluddin Haqqani, and now run by his son Siraj. It is closely linked to al-Qaida.

At the same time the group has been targeted by special forces ground raids, with US officials saying privately they believe the Haqqani network has been hurt by the joint tactics.